1. Field of the Invention
The present invention pertains to a work or material handling machine having rotary barrels containing works or materials to be surface-finished, stirred, mixed or milled, and more particularly to a centrifugal rotary barrel-type finishing machine which causes a set of barrels to both turn on their respective axes and revolve around their common central axis, placing the contents under the resulting centrifugal force and thus subjecting them to the surface-finishing or polishing, stirring, mixing, or milling process, wherein means is provided for automatic charging and discharging of works or materials into and out of the barrels.
2. Description of the Prior Art
The rotary barrel finishing machine of the kind disclosed herein is known, which includes a pair of upper and lower turrets between which a number of work finishing tubs are arranged. In this prior art machine, the turrets are rotated at a high speed while the tubs on the turrets are also turned around on their respective axes, thus producing a centrifugal force equal to several or several ten times the gravitational acceleration. In this way, the contents within each of the individual tubs are placed under the action of the produced centrifugal force, so that a circulating flow of the contents can take place within the tubs. The same machine has applications such as surface-finishing, stirring, mixing and milling, and provides a high working efficiency in those applications. Despite its high working efficiency, however, the machine has a problem in the charging and discharging of the materials into and out of the finishing tubs on the turrets, the operations of which require much labor and time. In order to solve the above problem, automatic charging and discharging methods have been studied in various ways. The solutions that are now practiced include the provision of tiltable tubs whereby the tilling of the tubs allows the discharging of the contents, and the provision of the tubs each equipped with a removable cover. Neither of the above solutions is satisfactory, however, since the first solution requires a complicated or sophisticated mechanism to permit a tilting of the individual tubs, and the second also requires a complicated mechanism because of the need of removing the covers away from the machine. Consequently, both of the solutions result in a very costly machine construction.